from __future__ import annotations


def m_to_mm(v: float) -> float: return v * 1000.0
def mm_to_m(v: float) -> float: return v / 1000.0
def kN_to_N(v: float) -> float: return v * 1000.0
def N_to_kN(v: float) -> float: return v / 1000.0
def deg_to_rad(v: float) -> float:
    import math
    return v * math.pi / 180.0
def rad_to_deg(v: float) -> float:
    import math
    return v * 180.0 / math.pi


def wind_speed_to_pressure(v_m_s: float, air_density_kg_m3: float = 1.25) -> float:
    """风速-风压换算 q = 0.5·ρ·V²，返回 kPa。"""

    q_Pa = 0.5 * air_density_kg_m3 * (v_m_s ** 2)
    return q_Pa / 1000.0


